I've played a lot of PvP with my fleet. Some of it for Dilithium, and others for training. Everyone had a way to recharge their shields, making my quantum torpedoes bad. My healing on a Science Odyssey was always more than twice my damage.
Once I've stumbled upon the Transphasic torpedo launcher by way of Breen, I've made use of it, and have seen more damage from my character than ever before. The enemy's ship's hull was degrading fast from a good High Yield, and for a decent DPV. Now, Instead of 200,000 Dmg/600,000 Heal, I'm dishing out 800,000 Dmg/400,000 Heal. The heal change was from my change of BOFF skills, though. More efficient.
Final Verdict: Transphasics are the most powerful torpedoes a man can use.

Quantums are still better, time a salvo when shields drop. My tac officer can get repeated 28k dmg torpedos back to back fully buffed. Shields already reduce torpedo dmg, then most people run dmg resistant shields, so by time your transphasics get any benfit from hitting a shield its marginal.

And if you hit someone with shields down with trans you get 0 benfit. Quantums can crush shields and hull if used right. Trasphasics sorta work on torpedo boats using tons of projectile doffs but you are still not usually as effective and even less so when shields drop.

I do not see how. By the time the Quantum?s can fire with shields down Transphasics have already done more than enough damage to outpace Quantums. Normally Transphasics end up killing the target well before Quantum?s.

What I mean is 1 Transphasics salvo on shields and 1 salvo on hull without shields does more damage than a timed Quantum salvo on hull.

The extra punch through power to shields of the transphasics seems better on the surface. But when you do the calculations to how much damage you actually get through shields with transphasics (I have done the calculation) it comes out to less than 1000 damage. So if you slap THY on there you get a little more... if a transphasic goes to the hull you lose the potential damage of other torpedoes. Now, quantums. If you are good at the timing you can do far more damage than a transphasic. One quantum to the hull will outweigh transphasic's extra penetration. And then you've also got lots of people running around with MACO shields, which are resilient shield arrays. so the bleedthrough is reduced even more. In the end quantums really are going to be better. You aren't going to be one-shotting cubes in your impenetrable Intrepid class with transphasics like Voyager.

I am the STO Lorax. I picked myself up and left, until the day the fun is replanted.

The extra punch through power to shields of the transphasics seems better on the surface. But when you do the calculations to how much damage you actually get through shields with transphasics (I have done the calculation) it comes out to less than 1000 damage. So if you slap THY on there you get a little more... if a transphasic goes to the hull you lose the potential damage of other torpedoes. Now, quantums. If you are good at the timing you can do far more damage than a transphasic. One quantum to the hull will outweigh transphasic's extra penetration. And then you've also got lots of people running around with MACO shields, which are resilient shield arrays. so the bleedthrough is reduced even more. In the end quantums really are going to be better. You aren't going to be one-shotting cubes in your impenetrable Intrepid class with transphasics like Voyager.

Are you using the old shield pen numbers? Not sure I can get my damage that low even if I strip off all my damage boosts. Your calculations look wrong to me.

A MACO shield still means a Transphasics has just over 40% Bleedthough.

EDIT:
I am going pop in game and test out Transphasics x2 High yields to see if I am wrong. Will post damage here, could you post your Quantum damage hull numbers?

I don't think he's arguing that two loadouts of the same rank (i.e. standard phasics/quantums or HY phasics/HY quantums) are in favor of quantums when it comes to bleed. Rather it's that the utility of phasics against bare hull is weak compared to quantums.